Damper means and draft regulating means for furnaces



June 19, 1934. M. s. ALEXANDER DAIPER BANS ND DRAFT REGULATING IEANS'FOR FURNACES Filed Jan. 27. 1932 Patented June 19, 1934 PATENT OFFICEDAMPER MEANS AND DRAFT REGULATING MEANS FOR FURNACES I Morris S;Alexander, East Orange, N. J.

Application January 27, 1932, Serial No. 589,088

2 Claims. '(01. 126293) This invention relates to draft regulating meansfor furnaces in heating systems, such as steam and hot water heatingsystems, although it is adapted to be applied to furnaces used for otherpurposes, and it is the primary object of the invention to provideimproved means thermostatically actuated and controlled to actuate thedraft regulating means to produce a maximum amount of heat with aminimum consumption of fuel and effecting a complete combustion of thefuel, and to provide means for this purpose which is simple and cheap inconstruction and highly efiicient in use. 7

In regulating the draft of furnaces and the like a door to the ash pitbelow the firebox is provided with a damper to regulate the area of anopening in the door to admit air to the furnace below the grate of thefire box. There is also provided a damper in the connection pipe of thefurnace with a chimney flue for the discharge of the products ofcombustion, as well as a damper for an opening in said flue connectionpipe exterior of the furnace, and means are provided connected with thedamper for the ash pit opening and the damper for the opening in theflue connecting pipe exterior of the furnace whereby said dampers aresimultaneously actuated through thermostatically controlled and actuatedmeans to actuate the damper for the ash pit opening to open position andsaid flue pipe damper to closing position when the fire in the furnacegets low, and to actuate the damper for the ash pit opening to closingposition and said flue pipe damper to open position when the fire comesup, but only manually operative means has been provided for actuatingthe damper in the flue connecting pipe for regulating the connection ofthe furnace with the chimney flue, and it is a further object of theinvention to provide means to operatively connect the damper in the flueconnecting pipe with and actuate the same with the actuation of thedamper for regulating the opening in the flue pipe exterior of thefurnace and the opening to the ash pit, whereby when said flue pipedamper controlling the opening exterior of the furnace is actuated toclosed position and the damper for the ash pit opening is actuated toopen position, the damper in the flue connecting pipe to regulate theconnection of the furnace with the chimney flue is actuated to openposition and actuated to closing position when the damper regulatingflue pipe opening exterior of the furnace is actuated to open positionand the damper for the ash pit opening is actuated to closed p0 sition.

Other objects and advantages will hereinafter appear.

In the drawing accompanying and forming apart of this application Figure1 is a perspective view of a furnace showing the pipe connection thereofwith the chimney flue with an embodi-V ment of my improved damperactuating and draft regulating means applied thereto.

,Figure 2 is a side elevation of a furnace and chimney flue connectingpipe,-and partly in section to show the arrangement of dampers forregulating the connection of the furnace through said pipe and anopening to said pipe from the exterior of the furnace.

Figure 3 is a view looking at the top of Figure 2 and partly in sectionto show the arrangement and construction of the damper for regulatingthe connection of the furnace with the chimney flue; and

Figure 4 is an end elevation of the furnace and chimney flue connectingpipe looking at the right of Figure 2.

In the drawing I-have illustrated an embodiment of my invention inconnection with a conventional form of steam generating boiler B havinga door 5 for an opening to the fire-box, a door 6 fora clean outopening, a door 7 for an opening to the grate, and a door 8 for anopening to the ash pit, said latter door having an opening adapted to beopened and closed by a damper in the form of anauxiliary door 9pivotally connected at the upper edge portion to the door 8, as at 10,whereby said damper is adapted to be moved upward to open the openingand when it is moved downward closing said opening. I

The furnace is connected with a chimney flue by a pipe 11 for theexhaust of the products of combustion, said pipe having an openingthrough the wall to the atmosphere exterior of the furnace through abox-like structure 12 connected to the top of the pipe and the openingtherethroughis regulated by a closure plate 13, which is in the natureof a damper, hingedly connected at a marginal portion to the rear wallof the box 12, as at 14. v

The connection of the furnace with the chimney flue through the pipe 11is regulated by a damper 15, in the form of a disk having a diametersubstantially the same as the internal diameter of the pipe, said damperbeing carried by and pivotally supported by a pintle 16 extendingdiametrically of and attached to the damper with the opposite endsextending beyond the periphery of the damper and engaging diametricallyopposite perforations in the pipe, as at 17 in Figure 3, so that thedamper will have movement on a horizontal axis and in a plane coincidentwith the plane of movement of the damper 13. The damper 15 is weightedat the side above its pivotal support by securing thereto a weight 18 ofcrescent shape which is adapted to normally urge the damper from theclosed dotted line position to theopen full line position shown inFigure 2.

The dampers 9, 13 and 15 are connected with thermostatically andautomatically operated actuating means to control and regulate the draftof the furnace, and shown as comprising a diaphragm carrying casing 19connected at one side, in the present instance the lower side, with thesteam chamber of the furnace by a pipe 20 which also serves to supportthe diaphragm casing. A plunger connected to the opposite side, in thepresent instance the upper side, of the diaphragm is slidably extendedthrough an axial tubular extension of the diaphragm casing and has aconnection with one arm of a lever 20, as shown at 21 in Figure 1, thelever being pivotally carried intermediate its ends by a bracket 22shown as mounted on the furnace. The opposite arm of the lever isconnected by a cable or chain 23 with an ear extended from the damper 9for the opening to the ash pit, as at 24, and connected with the damper13 by a cable or chain 25 passing over suitably supported pulleys 26 andattached to the damper 13 at the end opposite to its hinge support, thedamper 15 for controlling the connection of the furnace with the chimneyflue through the pipe 11 being connected by a cable or chain 27 with thedamper 13, said chain being attached at one end to the damper 15adjacent the peripheral portion above its pivotal support, as at 28, andpassing over a pulley 29 rotatably carried by brackets 30 secured to andextending from the inner face of the front wall of the box 12 and thechain 27 being attached at the opposite end to the inner side of thedamper 13 in line with the connection of the cable 25 connecting saiddamper with the lever. The diaphragm is adapted to be actuated when thesteam reaches a predetermined temperature and pressure to cause anupward movement of the diaphragm in the diaphragm casing 19 and therebymoving the plunger 21 and the connected arm of lever 20' upward, theconnection 23 of the lever with the damper 9 for the ash pit openingmoving said damper to closed position, and said movement of the leversimultaneously through the connection 25 thereof with the damper 13moving said damper from the full line closed position to the dotted lineopen position shown in Figure 2, and through the connection 27 of saiddamper with the damper 15 moving said latter damper from the full lineopen position to the dotted line closed position shown in said Figure 2,thereby shutting off the draft through the ash pit opening and betweenthe furnace and chimney flue and opening the chimney flue to theatmosphere exterior of the furnace through the box 12. As the fire diesdown with a consequent reduction in temperature and pressure of thesteam the diaphragm in the diaphragm casing will be automaticallyreturned to its normal position facilitated by a weight 31 adjustablymounted on the lever arm to which the diaphragm is connected, saidweight being adjustable to cause the diaphragm and draft regulatingdampers to be actuated at variable temperatures and pressure of thesteam. As the diaphragm returns to its normal position the lever 20' isactuated and through its connections with the dampers 9, 13 and 15moving the damper 9 to open position, the damper 13 to closed posi tionand the damper 15 to open position, thereby admitting air to the gratebelow the fire-box and opening the draft from the furnace with thechimney flue through the pipe 11 which latter draft connection will notbe impaireddue to the opening to said pipe through the box 12 beingclosed by the damper 13.

To permit of the flow and exhaust of the prod nets of combustion, suchas gas, from the furnace through the pipe connection 11 with the chimneyflue when the damper 15 has been moved to closed position, the damper 15is provided with openings therethrough, in the present instance twoseries of three openings each arranged at opposite sides of the pivotalsupport of the damper, as at 32, and to retard said flow of the gas andthus effect practically a complete combustion of the gases tubularconical members 33 are secured at the larger ends in said openingsextended rearwardly of the damper in a direction away from the furnacetoward the chimney flue, said conical tubes also preventing a backdraft.

While I have illustrated and described the in vention in connection withthe draft regulating dampers of a steam generating furnace and ascontrolled by the variations in the temperature and pressure of thesteam, it will be obvious that i the invention is equally applicable tofurnaces in hot water heating systems, the diaphragm being actuated fromthe variations in the temperature and expansion of the water, and thatit may be also utilized in connection with oil or gas burners bycontrolling the actuation of a valve for con trolling the delivery ofthe oil or gas to the furnace.

Having thus described my invention, I claim:

1. In means for regulating the draft of furnaces, a pipe adapted toextend in a horizontal plane to connect a furnace with a chimney flue,said pipe having an opening through the wall at the top of the pipe, adamper having a diameter substantially the same as the interior of thepipe pivotally supported within the pipe to have movement on ahorizontal axis extending diametrically of the pipe and having a portionabove its pivotal support weighted and arranged to normally urge thedamper to pipe opening position, a closure member for the opening in thewall of the pipe to have movement on an axis parallel with the pivotsupport of the damper, and a flexible member within the pipe to connectthe damper with the closure member, the length of the flexible memberbeing such that when the closure member is moved to close the pipeopening the damper member will assume pipe opening position under theinfluence of its weighted portion, and when the closure member is movedto open the pipe opening, the damper member will assume pipe closingposition.

2. In means for regulating the draft of furnaces, a pipe to connect thefurnace with a chimney flue having an opening in the wall, a damperhaving a diameter substantially the same as the interior diameter of thepipe pivotally supported within the pipe to have movement on ahorizontal axis extending diametrically of the pipe and having aweighted portion at one side of its pivotal sup port arranged to urgethe damper to pipe opening position, a closure member for the opening inthe wall of the pipe pivoted to have movement on an axis parallel withthe pivot support of the damper, and a flexible member to connect thedamper with the closure member within the pipe, said flexible memberbeing of such length that when the closure member is moved to positionto close the pipe opening the damper will assume pipe opening positionunder the influence of its weighted portion, and when the closure ismoved to open the pipe opening the damper is simultan'eously moved topipe closing position.

MORRIS s. ALEXANDER.

